Process and apparatus for covering elastic filaments



Nov. 17, 1942,. R. A. GIFT, JR., arm. 2,302,543

PROCESS AND APPARATUS FOR COVERING, ELASTIC ,FILAMENTS Filed Aug. 9,;1941

M .2 mm

4 a n. i

A. m .3 m 6.13M 2 E s M 2 NEY Patented Nov. 17, 1942' PROCESS S PATENT OFFICE 2,302,543 AND APPARATUS FOR COVERING ELASTIQFILAMENTS N. J., assignors to Application 6 Claims.

The present invention relates to covering elastic filaments. More particularly, it relates to the covering 'of elastic filaments with one or more spirally applied elongate materials.

Elastic filaments, for example bare rubber threads, are provided with covers by passing a length of the filament from a supply roll, stretching the filament and passing it while stretched through a hollow revolving spindle which carries a package of elongate covering material which is applied around the filament, after the latter passes from the spindle, usually by being passed from the package through a flier or ring traveler and then laid around the elastic filament. If a second covering is desired, the elastic thread extends, while stretched, second revolving spindle which also carries a package of the same or a different covering material which is applied in the opposite direction over the previously-applied cover in the form of a spiral. Additional covers may be applied in this same manner if desired. The completely-covered elastic filament is then wound upon a suitable receiving roll, such as a reel, drum, or the like. During the covering operation the material forming the packages carried by the revolving spindles is gradually dissipated which, in turn, reduces the diameter of the packages and this is accompanied by changes in the maxim elongation of the covered elastic filament. Attempts have been made to compensate for this drop in maximum elongation of the covered filament by increasing the rate of passage of the filament through the spindles from time to time during a covering operation when it was noticed that the maximum elongation of the filament had changed. This type of operation has been entirely unsatisfactory since covered elastic filament produced in this manner is marked by sharp variations in the characteristics of the elastic filament occurring at indefinite points throughout the length of the filament. When a filament having such sharply-varying characteristics is utilized to knit a garment, such as a girdle, sock top or the like, the finished garment will .be of" inferior quality because of the occurrence of areas throughout the garment which are knit under different tensions from the remainder of the garment due to variations in the characteristics of the yarn. also be of inferior quality when manufactured from elastic yarn which varies in physical characteristics throughout its length.

It is an object of the present invention to provide a process and apparatus for covering 55 eral stepsand the relation Woven garments will Fila Robert A. Gift, Jr., and Robert F. Jessen, Trenton,

tex Corporation, New

York, N. Y., a corporation of New Jersey August 9, 1941, Serlal No. 406,232

through a elastic filamentary material which overcome all of the foregoing disadvantages.

It is also an object of the present invention to provide a process of covering elastic filaments which will produce an elastic filament which is uniform in physical characteristics throughout its length.

It is another object of the present invention to provide an apparatus capable of covering elastic filament so'that it will have substantially uniform physical characteristics throughout its entire length.

Other objects and advantages, if not specifically pointed out, will be apparent to those skilled in the art from the following detailed description of what are now considered the preferred forms of the invention.

The process of the present invention, in general, comprises passing an elastic filament through one or more hollow rotatable spindles bearing packages of elongate covering material, applying the elongate covering material about the filaments in spiral form, reversing the direction of application of each successive spiral when more than onecovering is used, and increasing the rate of passage of the filament through the spindles in accordance with a predetermined schedule as the elongate material is used from the packages to compensate entirely for any variation in maximum stretch of the finished covered filament which would tend to occur as the elongate covering material is used from the packages.

The apparatus of the present invention, in

general, comprises means for supplying elastic filamentary material to a tension roll, a second tension roll to which the filament is passed, a variable speed mechanism for driving the two tension rolls so' that the ,second tension roll rotates at a definitely greater rate of speed than the first tension roll, one or more hollow spindles through which the elastic filament passes while passing from one tension roll to another, means for supporting a package of elongate covering material on each of said spindles, means for rotating 'each of the spindles to apply the elongate covering material in spiral form about the elastic filament, and means operated in accordance with a predetermined schedule for' progressively increasing the rate of passage of the elastic filament through the spindles without varying the difference in the speeds of the tension rolls.

The invention accordingly comprises the sevi one or more such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts which are adapted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims.

An apparatus which is preferred for carrying out the process of the present invention is diagrammatically illustrated by the accompanying drawing in which certain of the parts are broken away for the purpose of more clearly illustrating the invention. Referring to the figure, the apparatus comprises a suitable frame structure which. is composed of two end plates 2 (only one of which is shown) suitably joined by cross rails 4. A cross rail in the form of an inverted channel member 6 supports a plurality of spindles 8 for rotation in suitable bearings I6. Each of the spindles 8 is driven by means of a rigidly connected whirl I2 by means of a band It driven by a pulley I6 carried by a driven shaft ll. The spindle illustrated is provided with a suitable filer I8 and carries a package of elongate covering material which may be textile thread 26. The second channel 22 positioned beneath the channel 6 carries any desired number of spindles 24 which are identical in all respects to the spindles 8 except that they are each driven in an opposite direction to the spindles 8 through the medium of a whirl 26 rigidly. carried by the spindle 24 and a band 28 driven by a pulley 36 carried by a driven shaft 82.

A spool 84 carrying a supply of elastic filamentary material 36 is suitably rotatably supported by a suitable support such as a pirn 88. A cone, drum or other desired holder for the elastic filamentary material may be used if desired. The elastic filament 86 is led through a suitable guide 46 and is passed several times around a friction roller 42 rigidly carried by a positively driven shaft 44. From the friction roller 42, the elastic filament 86 is pased up through a lower hollow spindle 24 and then through an upper hollow spindle 8 and then passed several times around a friction roller 46 rigidly carried by a positively driven shaft 48. The shafts 44 and 48 are driven by a suitable mechanism (not shown) so that the peripheral velocity of the roller 46 is any desired amount in excess of roller 42 to impose any desired tension upon the filament 36 between the rollers 42 and 46 within the stretch limits of the elastic filament. As the stretched elastic filament passes out of the hollow spindle 24 the elongate covering material 56 carried by the lower spindle is laid around the filament 36 in spiral form by the rotation of the spindle and the resulting rotation of the filer 52. The filament having one spiral v of the pulleyare urged toward each other covering of elongate material thereon then passes through the hollow spindle 8 and after it emerges therefrom receives'a second spiral covering of elongate material 26 from the upper spindle. The covered elastic filament 54 is then passed through a suitable traversing guide 56 and is wound upon a reel or the like support 58 which is rotatably mounted upon the frame 2-2 and positively driven preferably by the same source as that used to drive the shafts 44 and 48.

The apparatus for driving the shafts 44 and 48 and the shaft 66 of the reel 58 includes a positively rotated shaft 62 which is driven by a suitable prime mover and carries a split pulley 64 for rotation therewith. The split pulley 64 is a variable diameter pulley of a type well known under a suitable elastic pressure furnished by a spring. A suitable pulley of this type is sold by the Equipment Engineering Company, Minneapolis, Minnesota, as Hilo pulley No. 130. The variable diameter pulley 64 drives a second V type pulley 66 by means of a v belt 88. The pulley 66 is rigidly carried by a shaft I6 which through suitable mechanism (not illustrated) drives the shafts 44, 48 and 66.

A plate I2 is pivoted at 14 to some suitable portion of the frame structure and has an idler pulley 16 mounted for rotation thereon on stub shaft I6. The pulley I6 receives the V belt 68 and the position of pulley 16 controls the effective length of the belt and causes the belt 86 to ride at a definite position on the said variable diameter pulley 64 so as to drive the pulley 66 at a predetermined speed.

The plate 72 has pivoted thereto a nut 86 which is received on a threaded shaft 82 mounted for rotation in a suitable portion of the frame 84 and prevented from longitudinal movement by a pair of suitable thrust collars '88. The shaft 82 carries for rotation therewith at its outer end a toothed wheel 88.

A shaft 96 suitably mounted for rotation on some desired portion of the frame is positively driven from some relatively slow moving element of the covering machine, for example from the reel shaft 66, through the medium of a pulley 62 rigidly carried by the shaft 96 and rotated by a belt 94 which is in turn driven by a pulley 95 mounted for rotation with the reel shaft 66. The shaft 86 has mounted thereon for rotation therewith a worm 86 which in turn drives a worm gear 98 mounted for rotation with a stub shaft I66 joumaled in a suitable bearing I62 carried by some portion of the machine frame. The 'shaft I66 drives a second stub shaft I64 through the medium of a suitable reducing gear which is illustrated as comprising a small gear I66 and a large gear I68 rigidly connected to the shafts I66 and I64, respectively. The shaft I64 is suitably mounted for rotation in a bearing H6 suitably carried by the frame and has rigidly mounted at its outer end a sprocket I I2. The sprocket II2 carries a chain II4 which passes at its lower end around an idler sprocket I16 carried 'for rotation with a shaft H6 suitably mounted for rotation in a portion of the frame I26 and prevented from end-wise movement by suitable thrust collars I22.

The chain H4 is in the natureof a pattern chain in that it has lugs or risers I24 removably attached at predetermined points thereon. As each riser passes the toothed wheel 88 it rotates it the distance occupied by one tooth on its circumference. In this manner the shaft 82 is rotated at predetermined intervals through a definite distance which threads the nut 86 to the right as viewed in the figure and rocks the plate I2 in a counterclockwise direction about its pivotal point 14, thereby loosening the belt 68 and permitting the belt to seek a position on the pulley 64 at a greater distance from the axis of the shaft 62 so as to increase the effective diameter of the pulley 64 and thereby drive the shaft 16 at an increased rate of speed. This increased rate of speed in turn causes the shafts 44 and 48 to revolve at progressively higher speeds but to maintain the same difference between their speeds.

The points at which the risers I24 are placed toothed wheel '88 along the chain H4 are determined by removing the belt 94 and covering a run of elastic filament and thereafter measuring the maximum stretch in the filament at suitable intervals, for

example, every five feet along the filament and part by the length of the chain H4 and in party by the speed of the shaft I04 relative to the speeds of the shafts 44 and 48. It is to be noted that the speed of the reel shaft 60 increases as the speed of the shafts 44 and 48 increase so that the increase in the rate of passage of the filament 36 through the machine is an accumulative operation. If desired, additional speedreducing gears may be inserted. in the train between the shaft 90 and the shaft I04 so as to reduce the speed of the chain H4 to one complete revolution during the course of a run which is determined by -the length of time required to use the covering material from the spindle packages carried by spindles 8 and 24. -When this latter arrangement is used the number and positions of the risers I24 will be determined as previously explained and placed so as to bring about the desired speed changes in the shafts 44, 48 and 60. Here again the shaft 60 increases in speed as the shafts 44 and 48 increase in speed so as to make the speed increase accumulative.

An alternative manner of positioning the risers on the chain H4 comprises removing the belt 94 as above explained and manually turning the when a change in the rate of passage in the filament through the spindle is believed necessary. Each time the toothed wheel 88 is turned the chain H4 is moved a corresponding amount and the links Whose risers would have engaged the toothed wheel 88 had there been risers present are suitably tagged. After several runs have been made in this manner so as to produce a covered elastic filament which is substantially uniform throughout its length in regard to maximum stretch, the tags on the links are replaced by risers and the entire series of risers are advanced a distance of one or two links along the chain one or two mal position of the chain at the starting point of a covering operation. In this manner, complete compensation for the effects on the elastic filament caused by dissipation of the covering material are anticipated and avoided.

The operation of the apparatus is apparent from the foregoing description. It is to be understood that the need for a change in the rate of passage of the elastic filament through the spindles 28 and 24 is anticipated by the apparatus and the change in speed is executed so as to maintain the covered elastic filament substantially' uniform in regard to max mum stretch instead of waiting until a change in maximum stretch occurs and thereafter increasing the speed of passage of the elastic filament through the spindles for the purpose of offsetting the then existing variation in physical characteristics.

the chain by advancing links relative to the norfor the purpose of illustration,

stood that two or three or more spindles may The process and apparatus of the present invention make it possible to produce a covered elastic filament which is uniform in regard to stretch characteristics throughout a given run on a machine which means that all of the elastic filament produced can be made substantially uniform in regard to physical characteristics because conditions for all of the runs can be made the same and thereby produce the same quality covered elastic filament indefinitely.

The process and apparatus of the present in-- vention are capable of covering elastic filamentary material regardless of the substance from which the filament is formed. For example, the elastic filament may be formed from rubber, rubber latex, synthetic rubber, synthetic resins or mixtures of these various substances.

The elongate covering materi vl may comprise textile materials, for example spun threads, yarns and the like; strips of non-fibrous materials, for example Cellophane (cellulose hydrate), synthetic resins and other non-fibrous materials; metallic wires, or any other desired covering material. Although two spindles have been shown it is to be underbe utilized in the practice of the present invention to provide as many coverings as desired.

The covered elastic filaments produced in accordance with the process and apparatus of the present invention are capable of fabrication into articles such as wearing apparel or the like which are uniform in quality throughout, which thereby enhances the value of such elastic filamentary material and extends its uses throughout many fie ds.

Since certain changes process and in the constructions set forth, which embody the invention, may be made without departing from its scope, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

l. The process of covering elastic filaments comprising advancing an elastic filament while maintaining it under a predetermined stretch, applying one or more spiral coverings of elongate material about the elastic filament from one or more supply packages of the covering material, and increasing the rate of advance of the elastic filament without varying the stretch of the elastic filament in accordance with a schedule predetermined by observation of the effect on the maximum stretch of the covered filament which accompanies d ssipation of the covering material from the supply package, so as to bring about the increase in the rate of advance of the elastic filament before said effect occurs, whereby the maximum stretch of the covered elastic filament remains substantially uniform throughout the length of the covered filament.

2. A machine for covering elastic filaments comprising means for advancing an elastic filament while stretching it a predetermined amount,

means for applying one or more covers of elongate in carrying out the above pendent upon the decrease in diameter. of the supply packages of covering material.

3. In an apparatus for covering elastic filaments, the combination of means for-advancing an elastic filament while stretching it a predetermined amount, means for driving the advancing means, means for supporting a package of elongate covering material and for applying material from the package in a spiral about the advancing stretched filament, and schedule control means for continuously varying the rate of operation of the driving means .for the filament advancing means to increase the rate of advance of the filament without changing the stretch in the filament and in accordance with a predetermined schedule, dependent upon the decrease in di-. ameter of the package of covering material.

4. The process of covering elastic filaments comprising advancing an elastic filament while maintaining it under predetermined stretch, aplying one or more spiral coverings of elongate material about the elastic filament from one or more supply packages of the covering material,

' and increasing the rate of advance of the elastic filament without varying the stretch of the elastic filament in accordance with a schedule predetermined by making a covering run extending from a full supply package of covering material to a completely dissipated supply package of covering material, ascertaining the variations in the maximum stretch of the covered elastic filament at definite points throughout the length of the filament and the amount of increase in the rate of advance of the elastic filament required at each point to compensate for the respective variation in the maximum stretch of the filament, and advancing the points at which the increases in the rate of advance of the elastic filament are to be made sufllciently to cause said increases to be made in advance of the said points whereby the maximum stretch' of the covered elastic filament remains substantially uniform throughout the length of the covered filament.

5. An apparatus for covering elastic filaments comprising a pair of rotatable members for receiving and advancing the elastic filament, variable speed means for driving the filament advancing members, means for supporting a package of elongate covering material and for applying material from the package in a spiral about the advancing filament at a point between said supporting and advancing members, and means for increasing the rate of operation of said vari- 'able Speed means to increase the rate of ad- Vance of the filament in accordance with a predetermined schedule, dependent upon the decrease in diameter of the package of covering material. J

6. An apparatus for covering elastic filaments comprising a pair of rotatable members for receiving and advancing an elastic filament, variable speed driving mechanism capable of step by step speed variation for driving said rotatable members, means for supporting a package of elongate covering material and for applying the material from the package in a spiral about the advancing filament between saidrotatable members, a pattern chain, mean for rotatably supporting the pattern chain, means for-driving the pattern chain at a definite instantaneous speed relative to the instantaneous speed of one of said rotatable members, and risers carried by said pattern chain at points spaced so as to bring about step by step variation in the speed of the variable speed driving means and said rotatable members so as to increase the r'ate of advance of the filament in a predetermined manner as the covering material is used from the supply package. p

ROBERT A. GIFT, JR. ROBERT F. JESSEN. 

